Protective means for deep well packers



March 14, 1939. R c. BAKER 2,150,310

I PROTECTIVE MEANS FOR DEEP WELL PACKERS Filed Dec. 12', 1938 JNVENTOR. M (5 M ATTORNEY Patented Mar. 14, 1939 UNITED STATES PATENT OFFICE PROTECTIVE MEANS FOR DEEP WELL PACKERS Application December 12, 1938, Serial No. 245,236

7 Claims. (01. 166-1) This invention relates to devices for enclosing and protecting deep well packers while the same are being lowered into a well casing.

Many well devices of the general character of 5 packers are so constructed and have incorporated in their design such exposed parts and operating mechanisms as to be exceptionally liable to damage or premature operation while passing through a well casing. In many instances pack- 10 ers or cement retainers are provided with prese't mechanisms which are susceptible of being prematurely tripped or of becoming clogged and rendered inoperative by heavy mud, drilling detritus, or pieces of foreign materials contained in 15 the mud-water present in the well. Besides being subject to undesirable damage, such exposed parts often cause the device to become caught in a casing, particularly at the joints thereof, this being especially liable to occur in wells which are crook- 20 ed or slantto an appreciable degree.

Further, during transportation to a well and while on an outdoor tool rack or other place of storage awaiting use in a well, such well devices are subject to injury, rust and corrosion and to rapid deterioration of such rubber and the like packing as may be included in their construction.

It is, therefore, the object of my present invention to provide a protective shell adapted to be applied to a well device at any desired time 30 before use thereof in a well, .said shell being formed to constitute an enclosing housing protecting said deviceagainst injury, rust and corrosion prior to'its use in a well, and against damage and premature operation while being 35 lowered in a well by a casing or tubing string, and adapted to be subsequently removed from said well device by pressure of fluid pumped down the casing or tubing string.

In practive I prefer to construct the protective 40 housing in the form' of a relatively thin sheet metal cylindrical jacket having a guide-shaped lower closed end in the shape of an inverted v truncated cone. This end is provided with a valve. The other end is open so that it may be 45 slipped -'over the well device until its upper rim portion extends slightly beyond the top of said device. With the protective housing thus positioned, its upper rim portion, or tangs formed thereon, is crimped inwardly sufficiently to maintain the housing. in place, but at the same time not to such a degree as to prevent said housing being forced off the well device by fluid pressure.

The invention is exemplified in the following description and illustrated by way of example in 55 the accompanying drawing, in which:

Fig. 1 is a perspective view illustrating the protective shell or housing of the present invention as it is applied-to a well device for shipmentor for storage prior to use in a well.

Fig. 2 is a vertical section illustrating a well 5 device with the protective housing applied thereto and being lowered into a well casing.

Fig.3 is a vertical section showing in elevation the well device at a position of use and the protective housing being forced therefrom.

Fig. 4 is a perspective view similar to the top portion of Fig. 1, but illustrating. a modified form of retaining means at the upper rim of the protective housing.

While it is obvious that the protective housing of my present invention may be applied to various types of well devices affording an initial through circulation of fluid, I have, by way of example, shown said housing as it is used in connection with a cement retainer of the character disclosed in United States Letters Patent No. 2,121,051, issued June 21, 1938 to Thomas M. Ragan and Clarence E. Burt, to which patent reference may be had for a more detailed description thereof.

For the purpose of the present disclosure, it will be sumcient to state that such cement retainer A is attached to the lower end of a casing or tubing string B and lowered into a well to a position of use. This device includes in its construction av tubular body I!) providing an initially open bore H through which circulation fluid may be pumped. 'I'his'body carries a rubber sleeve packing I2 and opposed slips l3 and H which will be subsequently expanded to grip the wall of the well casing to support the retainer therein. The packing sleeve l2, of this specific form of cement retainer, is expanded by the pressure of the fluid entering behind said. sleeve through lateral passages i5. 40

The means which I employ to protect this cement retainer, or any other similar device adapted to be lowered into a well by a casing or tubing string, comprises a cylindrical shell C preferably formed of relatively thin sheet metal, such as galvanized iron, and having a lower end of inverted truncated cone shape. tending to guide the housing and its contained well device safely down the well. Above its lower cone end, this shell or housing C is normally undeformed and is of uniform diameter so that it may readily be "slipped over the cement retainer A, and is of such length that its upper rim portion will initially extend slightly above the top of the contained cement retainer.

To retain the housing or container C on the cement retainer A, against accidental displacement or removal therefrom, I form the upper rim thereof with suitable releasable retaining means. In the form shown in Figs. 1, 2 and 3, I preferably initially vertically slit the rim portion of the housing at circularly spaced intervals to form a series of tangs, and after the housing is in place upon the well device, I bend each alternate tang l6 inwardly and downwardly over the upper marginal edge of said well device.

The bottom wall of the housing C has an inlet opening I! formed therein and defining a valve seat, and is provided with an inlet valve l8 ar-' ranged to cooperate with said valve seat to control flow of fluid into the housing. While various types of valves may be employed for this purpose, I prefer to use a flapper type valve formed of a flexible material, such as rubber or leather, and secured at one end to said bottom wall with its free end provided with a suitable reenforcing weight disc 19.

In practice, the protective housing C may be applied to a well device as shown'in Fig. 1, prior to shipment thereof, or it may be thus applied after the device is connected to the casing or tubing string B and just prior to its trip down a well. During the lowering into the well of the cement retainer A with the enclosing protective housing C, the inlet valve l8 will open, as shown in Fig. 2, to allow passage of well fluid into the housing and upwardly through the associated cement retainer A.

When the cement retainer A reaches its position of use, fluid is circulated down the casing or tubing string B and through the cement retainer and into the lower portion, of. the housing C. This downward flow of the circulation fluid will close the inlet valve I8 of the housing and build up a. pressure therein suflicient to drive said housing downwardly oil the cement retainer. In so doing, the retaining tangs H5 at its upper end will be straightened by such downward movement to release the housing, as shown in Fig. 3. The released housing C will drop to the bottom of the well bore, and, being constructed of relatively soft metal, may subsesequently be readily side-tracked or drilling up during a later drilling operation, or may later be fished from the well if desired.

In Fig. 4 I have illustrated the upper portion of a protective housing having a modified form of retaining means. In this instance the upper rim of the housing is not slit as is the housing of Figs. '1 to 3, but is pressed or rolled inwardly to form a relatively pliable retaining bead or flange 20.

From this disclosure it will be evident that I have provided a practical and effective means which may readily be applied to a well device and which affords an adequate means for protecting such device against undue wear or faulty operation while being lowered into a well, and against injury and corrosion while exposed to the weather prior to use.

While I have described and illustrated the invention in a preferred form of embodiment, it is to be understood that various changes may be made therein without departing from the invention as defined in the appended claims.

Havingthus described my invention, what I claim and desire to secure by Letters Patent is:

1. A protective housing comprising a cylindrical shell adapted to be slipped over a well device, said shell having at its upper end a yielding retaining means adapted to be engaged with said well device, and a closed lower end in which an inlet opening is formed, and an inlet valve controlling said opening.

2. A protective housing as defined in claim 1, in which the shell is formed of relatively thin sheet metal and is provided at its upper end with a series of relatively pliable tangs adapted to be bent inwardly over an upper edge of a well device to form said yielding retaining means.

3. A protective housing as defined in claim 1, in which the shell is formed of yielding sheet metal and has a continuous upper end adapted to be pressed or rolled inwardly over an upper edge of a well device to form a relatively pliable internal bead or flange serving as said yielding retaining means.

4. In combination with a well device adapted to be lowered into a well at the lower end of a casing or tubing string and through which fluid may be pumped, a protective housing enclosing said well device and retained thereon by yielding means, said housing being provided with an inlet opening through which well fluid may flow into said housing and upwardly through the well device during downward travel thereof, and an inlet valve controlling said inlet opening and adapted to be closed by the pumped fluid and cause a building up of pressure within the housing' sufficient to overcome said retaining means and force said housing from said well device.

5. In combination with a well'packer, of a container having an external contour substantially complemental to the contour of the packer and having an open and into which the packer may be inserted, the other end of said container being closed against fluid moving in the direction thereof from Within the container, and releasable means yieldingly connecting said container to said packer.

6. In combination with .a cement retainer generally cylindrical in outline, of a cylindrical container of a diameter to enable it to snugly fit over said cement retainer, one end of said container being open whereby said retainer may be projected thereinto and be enclosed thereby, the other end of. said container being closed against the force of fluid exerted within said container, means for releasably connecting said container to said retainer.

7. In combination with a cement retainer generally cylindrical in outline, of a cylindrical container of a diameter to enable it to snugly fit over said cement retainer, one end of said container being open whereby said retainer may be projected thereinto and be enclosed thereby, the other end of said container being closed against the force of fluid exerted within said container,

means for releasably connecting said container to said retainer, said container having a valve in its closed end opening when the fluid pressure from the exterior of the casing exceeds that at the interior of the casing and closing when the pressure of the fluid interiorly of the container is greater than that at the exterior thereof.

REUBEN C. BAKER. 

